Syslog

Syslog-ng install

apt-get install syslog-ng

Example of /etc/syslog-ng/syslog-ng.conf:

Comment kernel source out as we are in a vserver:

   source s_all {
       #file("/proc/kmsg" log_prefix("kernel: "));

Enable logging per remote host

   source net { udp(ip(192.168.x.xxx)); };
   destination df_zeus    {   file("/var/log/remote-zeus.log"    owner("root") group("adm") perm(0640)); };
   destination df_public  {   file("/var/log/remote-public.log"  owner("root") group("adm") perm(0640)); };
   destination df_private {   file("/var/log/remote-private.log" owner("root") group("adm") perm(0640)); };
   destination df_ns0     {   file("/var/log/remote-ns0.log"     owner("root") group("adm") perm(0640)); };
   destination df_sql     {   file("/var/log/remote-sql.log"     owner("root") group("adm") perm(0640)); };
   destination df_others  {   file("/var/log/remote-$HOST.log"   owner("root") group("adm") perm(0640)); };
   filter f_zeus    { host(192.168.x.xxx); };
   filter f_public  { host(192.168.x.xxx); };
   filter f_private { host(192.168.x.xxx); };
   filter f_ns0     { host(192.168.x.xxx); };
   filter f_sql     { host(192.168.x.xxx); };
   filter f_others  { not host(192.168.x.xxx) and not host(192.168.x.xxx) and not host(192.168.x.xxx) and not host(192.168.x.xxx) and not host(192.168.x.xxx) };
   log { 
       source(net);
       filter(f_zeus);
       destination(df_zeus);
   };
   log {
       ...

Manual

• http://www.balabit.com/products/syslog_ng/reference-2.0/syslog-ng.txt

Resources & Credits

• http://www.linux-france.org/prj/inetdoc/articles/devmgmt/devmgmt.log.html (FR)

   source net {
       udp(ip(192.168.2.1));
       };
   filter f_sw1 { 
       host(192.168.2.2) and level(info,notice,warn,crit,err);
       };
   destination d_net_devices {
       file("/var/log/$HOST.log" owner("root") group("adm") perm(0640));
       };
   log { 
       source(net);
       filter(f_sw1);
       destination(d_net_devices);
       };

Resources & Credits

• http://www.linux-france.org/prj/inetdoc/articles/devmgmt/devmgmt.log.html (FR)

fwlogwatch

-A INPUT -s 192.168.2.2 -p udp --dport 514 -m state --state NEW -j ACCEPT

Logcheck

apt-get install logcheck logcheck-database

In /etc/logcheck/logcheck.conf:

REPORTLEVEL="paranoid"

Filtering

I have many such messages in the vserver:

pam_limits[863]: setrlimit limit #6 to soft=-1, hard=-1 failed: Operation not permitted; uid=0 euid=0

Not sure why, probably because vserver max limits are reduced.
To get rid of it, comment the line in /etc/pam.d/cron:

#session    required     pam_limits.so

For common imapd timeouts:

/etc/logcheck/ignore.d.paranoid/local-imapd
^\w{3} [ :0-9]{11} [._[:alnum:]-]+ imapd: TIMEOUT, user=[a-z]+, ip=\[[:.0-9a-f]+\], headers=0, body=0, rcvd=[0-9]+, sent=[0-9]+, time=[0-9]+, starttls=1$